Displaying 1 result from an estimated 1 matches for "previous_id".
2011 Sep 22
2
Numbering entries for each subject
...thanks in advance
Toni
A <- data.frame(ID=c('A','A','A','A','B','B','B', 'C','C','C','C','C'))
ID
1 A
2 A
3 A
4 A
5 B
6 B
7 B
8 C
9 C
10 C
11 C
12 C
A$Session_ID <- 0
previous_ID <- ''
current_index <- 1
for ( i in seq(1,nrow(A)) )
{
if (A$ID[i] != previous_ID)
{current_index <- 1}
A$Session_ID[i] <- current_index
previous_ID <- A$ID[i]
current_index <- current_index + 1
}
ID Session_ID
1 A 1
2 A 2
3 A...